Superstars from all genres collided on Friday night (September 20) for the kickoff of the 2019 iHeartRadio Music Festival. Beyond the energetic sets, which saw Green Day return to the festival after Billie Joe Armstrong's infamous 2012 rant, Camila Cabello live debut her new singles and an eye-popping performance from Cage the Elephant, Night 1 of the Sin City affair also saw special appearances from Christina Aguilera, Taye Diggs and more. If you missed out on the action, we have you covered with a list of the show-stopping moments.

Green Day Returns To iHeartRadio Music Festival After Infamous 2012 Rant

Seven years after Green Day trashed their guitars (and Justin Bieber) at the 2012 iHeartRadio Music Festival, the rock group returned to Sin City for the kickoff of this year's installment. Introduced by Ryan Seacrest and Christina Aguilera, the band went through a handful of their greatest hits, with a surplus of shoutouts to the audience. Among the usual suspects included new single, "Father of All," "Holiday," "Basket Case" and "Boulevard of Broken Dreams." The group, which recently announced their "Mega Hella Tour," alongside Weezer and Fall Out Boy, also turned their rifle on President Donald Trump when Armstrong switched a line in "American Idiot" from "I'm not a part of a redneck agenda" to "I'm not a part of a MAGNA agenda." It also happens to be the 15th year anniversary of the 2004 smash.

Tim McGraw Honors The Cars Frontman Ric Ocasek

Tim McGraw took his love for The Cars to his set when he performed his cover of their 1984 hit "Drive" as a tribute to the band's late frontman Ric Ocasek, who just passed away on Sunday (September 15), as well as the band's original lead singer Benjamin Orr.

"All of us that you see on stage tonight, all of us artists and songwriters, we're all inspired by things that move us," the country titan told the crowd at Las Vegas' T-Mobile Arena. "We're a product of our imagination and a product of the things that we grew up hearing and the things that we grew up loving and the things that we grew up making love to and making life to and we're losing a lot of good ones."

McGraw went on to recall his college days, where he would sit with his guitar on the front steps of his fraternity house and realize that he had a way with the ladies — as long as he had a guitar in his hands. "This next song, when I say we're a product of what we listen to, we all learn from each other and we're all inspired by each other. This is one of the songs that inspired me and I hope you like our version of it," he continued. Immediately after, the titan took on the classic and ended the number on a somber note as a backdrop featuring images of Ocasek and Orr appeared on the jumbo screen.

Camila Cabello Live Debuts New Singles, "Shameless" And Liar"

Camila Cabello's decision to roll out two new singles, "Shameless" and "Liar," prompted the pop star to offer debut performances of the tracks during her set. After a performance from Lil Nas X, the former bandmate took the stage in a sparkling pink number to sing the singles during her 20-minute set. While Cabello started things off with "Shameless," showcasing similar choreography to the official video, "Liar" saw the 22-year-old keep the energy high with her backup dancers. Elsewhere during her time on stage, which was also backed by a four-piece band, she performed "Never Be The Same" and a solo rendition of "Señorita," but a Cabello set wouldn't be a Cabello set without her breakout single, "Havana," and a very feisty dance break.

Cage The Elephant Released The Beast

Cage The Elephantfamously mention a captured animal in their band name, but at the 2019 iHeartRadio Music Festival, they released the beastin every way imaginable. The band put on an electric show for the crowd, and singer Matt Shultz made it all the more memorable with his epic performance. The set started with smoke filling the stage and pyro going off, then, Shultz, wearing a large hat and an eerie mask, started singing "Broken Boy," but that was just the start of how he released the beast. Once he moved on to their second song, "Ain't No Rest For The Wicked," he began to remove articles of clothing - the hat went, the mask, a chain he wore, a shirt layer and more.

From there, it got near chaotic. Matt seemed to fall off the stage and get lost in the audience - just what might happen to a wild beast that gets uncaged. If that weren't enough, he kept removing articles of clothing until all he was left wearing was in a unitard. Click here to see the full play-by-play!

Lil Nas X's Abs Stole The Show

Lil Nas X brought “Old Town Road” and his killer abs to the iHeartRadio Music Festival. The country-trap rapper hit the stage in a headline-making outfit, wearing a flame-filled blue, leather vest and pants set, along with matching shoes, that put his rock hard six-pack on full display. While his abs were the definite show-stopper, Lil Nas X's performance was also unforgettable.

The 20-year-old rapper gifted fans at T-Mobile Arena not one, not two, but three of his chart-topping hits as part of his two-part T-Mobile Magenta Moment. He kicked things off with his latest single, “Panini," before pausing his set and later returning to perform "Rodeo" and his hit record, “Old Town Road."

Backstreet Boys Reflect On Their 'Renaissance' During iHeart Festival Set

During their performance, the Backstreet Boys opened up about all of their recent success and, as they call it, it's been a "renaissance" for them. The guys said, "Three years ago, right here on the iHeart stage in Vegas, we made a surprise appearance with our friends Florida Georgia Line. Ever since that moment we've been on quite a ride as a singing group, as pop artists, as performers. And I feel like that that performance was kind of a jumping off point for the Backstreet Boys. Kind of a renaissance has occurred since then. Since that time we've had the pleasure of performing on the Las Vegas stage of our Las Vegas residency for two years. We celebrated 26 years as performers in a singing group."

"We recorded our ninth studio album, the DNA album; it debuted at number one. We were nominated for our eighth Grammy. And we are currently in the middle of our 'DNA World Tour,'" he continued. "I say all that, not to be braggadocios or pat ourselves on the back, but iHeartMedia [and] iHeartRadio is a big part of this renaissance that is happening right now. And we just want to acknowledge them and thank them for believing in us, believing in our music, helping us to continue our legacy. We're so proud to be a part of the music community, we're so honored to be here with you tonight."

To celebrate their renaissance, BSB performed some of their biggest hits and fan favorites including "Everybody (Backstreet's Back)," "The One," "I Want It That Way," and "Larger Than Life." The guys also performed their hit DNA lead single "Don't Go Breaking My Heart."

Halsey Performs 'Graveyard' For The First Time

Halsey’s performance was anything but a nightmare. For the 24-year-old singer’s set at T-Mobile Arena, she pulled out all the stops, performing a series of her hits, including "Gasoline," "Bad At Love," "Nightmare" and "Without Me." Halsey additionally treated fans to her first performance of her latest single "Graveyard," while outfitted in a body-hugging, colorful unitard and a sheer, green button-down.

Steve Aoki & BSB Recreate Emotional 'Let It Be Me' Video

Steve Aoki pulled out all the stops during his set at this year's iHeartRadio Music Festival. Between dance floor anthems, several guest performers and caking fans in the face, the producer/DJ did it all. Let's unpack everything that happened on stage during Aoki's performance, shall we? To kick off his set, Steve played several of his hits including his Louis Tomlinson collab "Just Hold On," his career-launching remix of "Pursuit of Happiness," and more. While the music was playing, four of the DJ's fans appeared on stage (along with four cakes) as he caked each person in the face, one by one.

After the cake-throwing, Monsta X came out to perform their collaboration "Play It Cool." The guys walked out to sing the song and showcase their incredible dance moves.

Next, Steve led the crowd in a gigantic dance party to his Alan Walker collab "Are You Lonely," followed by "Pretender" which features AJR. Then, he surprised everyone at T-Mobile Arena again when he brought out Darren Criss to perform "Crash Into Me," their Dave Matthews Band cover.

Finally, after playing his BTS mashup "Alamo Mic Drop," Aoki finished out his iHeartradio Music Festival set in an emotional way with the help of Backstreet Boys (who also hit the stage earlier in the night), performing their collaboration "Let It Be Me" — and basically recreated the song's tear-jerking music video.

While the actual music video played on a screen behind Aoki, BSB came out to sing the song. Then, at the very end, the couples from the visual, who have each overcome different obstacles for love, appeared on stage to help close night one of the festival out.

French Montana Turns The Heat Up With Hits

French Montana haad all of Las Vegas yelling his signature “haan." During his set, 34-year-old rapper performed a number of his fan-favorite hits. French came out the gate with a banger, beginning his set with "Intro," before transitioning into “Work,” “Shot Caller,” then “All the Way Up,” and “Loyal.” Bringing the crowd to its feet, the "Choppa Choppa Down" rapper went into the second half of his set full of energy performing “Ain’t Worried About Nothin,” and “Unforgettable.” To close out his performance, French gifted fans a few of his classics, including “Ocho Cinco,” “Pop That,” and one of his latest tracks “No Stylist.

Heart Taught Us 3 Very Important Lessons

Heart brought their beats to crowd, performing hits like "Magic Man," "What About Love," "Crazy On You" and "Barracuda," much to the delight of the audience. Not only did they treat everyone to a spectacular performance, they also taught them some things as well. Here are the three biggest lessons the crowd took from Heart's set:

1.What a lap dance is.

You read that right, but it might not be how you think. Before putting on a rocking rendition of "Straight On," singer Ann Wilson told the audience, "If you're standing up, you can always move your seventh chakra. If you're sitting down, you can still move it - we'll just call it a lap dance."

2. Lasers make everything cooler.

The crowd was totally into "Barracuda," but the green lasers shooting out from behind the band really took it to a new level.

3. The Wilson sisters are some of the most talented musicians in the business.

Most people's voices are shot after just a short conversation, but after performing live hundreds of times, Ann's chops are still top-notch. Meanwhile, Nancy has only gotten better on the guitar over the years, and considering she was already a phenom, that says a lot.

Hootie & The Blowfish Get Funky And Get Down

Hootie & the Blowfish entertained the huge crowd at the 2019 iHeartRadio Music Festival at the T-Mobile Arena in Las Vegas. The band performed hits like "Hold My Hand," "Let Her Cry," "Time" and "Only Wanna Be With You," which many people expected but were still thrilled to witness. The group then surprised everyone by playing the song "Hold On" off Imperfect Circle, their first new album in 14 years. However, what really surprised the audience was how Darius Rucker and the guys ended the set. It seemed like "Only Wanna Be With You" was their closer, but after the song ended, the band broke out a cover of Kool and the Gang's "Get Down On It."

Fletcher Hits Festival Territory — And Halsey Was Front Row To See Her

Even with an abbreviated two-song set, Fletcher brought the Sin City crowd her hit, "Undrunk," and its follow-up single, "If You're Gonna Lie." For the biggest year of her career, the rising pop star has officially moved into the festival territory and it seemed as if fellow Friday night performer Halsey was excited to see her sing since she snuck up to the pit of the venue during her set.

If you missed any part of the weekend, we've got you covered. Fans can re-live all of the epic performances and collaborations by tuning in to a televised special on The CW Network at 8 p.m. ET/PT on October 2nd and 3rd. And leading up to the official television special, The CW will also air an hour-long Best Of Special on Sunday, September 29th at 8 p.m. ET/PT taking a look back on all of the most iconic moments from the festival in its nine year history.